


Falling Behind

by skelerose



Category: Undertale (Video Game)
Genre: Alternate Universe - Underfell, Alternate Universe - Underswap, Depression, Horror, Hurt/Comfort, M/M, Psychological Trauma, Rating: M, Suicide Attempt, Underfell Papyrus, Underfell W. D. Gaster, Underswap Papyrus, Violence, W. D. Gaster is not related to Skelebros
Language: English
Status: In-Progress
Published: 2017-09-10
Updated: 2017-10-22
Packaged: 2018-12-26 03:33:41
Rating: Mature
Warnings: Graphic Depictions Of Violence
Chapters: 3
Words: 3,538
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12050430
Author URL: https://archiveofourown.org/users/skelerose/pseuds/skelerose
Summary: USPaps finds himself stuck with a certain Underfell duo.uspaps/ufpaps





	1. Chapter 1

Sitting there, were the bones of a man who had felt his fair share of misery and hatred. He sat, gazing at the clouds of smoke that rose to the ceiling after being exhaled from his nonexistent lungs. He could feel all things in this moment...heartache, strife and an ever so familiar physical pain that occasionally threw him onto the floor. The throbs of pain came in waves that crashed against his skull in rage were all but just a memory. He lived in pain and no matter the day, he never failed to disappoint himself drastically.

His attention drew towards his brother, standing in the doorway of their living room. He felt panicked, watching the figure of judgement cross his arms impatiently before speaking.

"Paps, you can't just smoke me out here." The kind but stern voice bellowed in his sensitive head. 

"Sorry." He replied, attempting to sound his sober. "I got a little carried away." 

He watched his brother walk into the room and step onto a sturdy coffee table, all while covering his mouth to protect him from the smell that invaded his senses. This allowed the shorter skeleton to reach the switch of the ceiling fan that hovered over them. 

"Headache today?" He asked. 

Papyrus grabbed the joint from his mouth and leaned forward, smothering it in the ashtray that harbored a mountain of ashes. "Yeah. Definitely."

His brothers only response to this was a simple, "don't think about it..." But he couldn't do that. It was in his nature to dwell on the negative energy that forever haunted his being for what seemed like an eternity. 

"- m alright, Blue." He stated coldly.

"Why don't you go out today?" Blue grabbed onto the curtains that blocked the sun and pushed them aside, he turned to watch the muggy air begin to dissipate in the sunlight. "Its warmer out than it has been." 

Paps only responded with a groan as he sheilded himself from the blinding light made worse by the snow on the ground. Today would be the day he would get out and force himself to live...or so he thought. 

"I don't really feel like doing much of anything today, Blue." He admitted as he allowed himself to sink into the couch.

"Paps, you didn't even sleep last night. You can't tell me you don't want to go out and do something."

He was about to respond until a loud "ding" came from their kitchen. "I'd better get that." Blue moved quickly from his spot by the window and came back holding a phone high enough to read it.

"Actually brother, Undyne just asked me if you would come to the lab...she needs help with something." 

No, he thought to himself. That's the last place I want to be. He drifted off for a moment, thinking about all the horrible nightmares that were created in that very same lab. The nightmares that kept him awake at night, afraid to nod off in pure terror that the darkness might encase him into the void again, and again, and again. 

"Brother?" He heard his dear sweet brother calling out to him, however that didn't negate the fact that he was terrified...(and high.) He felt himself replacing his brothers voice with that of the man's responsible for his fear. His own screams of pain echoed in his memory as Gaster, (oh how he wanted to kill himself at the remembrance of the name) tortured him nearly to death on a regular basis. 

Part of him wanted to go back to the lab in sheer curiosity. He hadn't seen the core since he watched Gaster fall (or rather be pushed) to his death. The explosion that followed should have killed him, (or so he had hoped.) Instead, he was permitted to continue his life, no longer being physically tortured. The effects, however, would last. 

"Brother??" Blue had lifted his brothers arms innocently, he knew this happened often. He could only stand there, waiting to ensure Paps wouldn't do try anything that would inflict harm on himself. Some nights, he would attempt to end the war in his mind and on these nights, Blue would intervene, knowing his older brother wouldn't remember a thing. 

Luckily, the effects of the smoking he had previously done helped immensely. He was able to snap out of the moment within a reasonable amount of time.

"Sorry." He looked away. "I'll go with you."

"Are you sure?" His brother gawked. "You don't have to, I know it can be hard."

"Nah." Paps responded, forcing himself to stand. "I think it would help to see the core still destroyed."

Cracking his back, he thought about escaping to his room and teleporting out...not allowing Blue to find him until Undyne no longer needed help. Instead, he became intrigued. "Any idea what Undyne needs from me?"

"Ehm...well she wanted us to visit her so that she could speak with you in person." Blue muttered as he gathered some belongings and placed them by the door. "She said it's totally up to you but she needs to talk to you, no question."

Paps immediately felt sick to his stomach. "Bro, I don't think..."

"Pappy..." The look Blue have him was chilling. "Its not something we can ignore...okay?"

He had an ugly feeling about this as he watched his younger brother gather supplies for the trek to the lab. 

"I can just teleport us there." Paps mentioned solely because he didn't want this taking up any more of his time.

"Are you feeling alright enough for that, Pappy?" 

"Yeah, it'll be fine." He lied. He waited for his brother to message Undyne that they were arriving before he teleported them just outside the lab. 

They were greeted with cameras tracking their movement along the massive door that would open only if the guests were given access. Just as Undyne appeared on the monitor, she allowed the door to unlock and greeted them. "I'm on the second level, room 4b."

Papyrus followed his brother in and felt the intense cold air that worked overtime to keep the lab at a cool, operating temperature. He wouldn't allow the familiar smell to overtake him and cause him to regain more unwanted memories of this horrible place. He acted as a shadow to his younger brother, quietly walking to the room that housed the royal scientist. 

"Hey guys." Undyne met them outside the room. "Thanks for coming." She nodded at Paps...He only stuffed his hands into his pockets in response.

"He thanks you for having us!" Blue lied in a kind hearted way.

"So, I'd really like to first start off by saying sorry." Her gaze met his as she spoke. "I know it was probably difficult for you to come here..."

"Papyrus...I have something I desperately need assistance with...I'm honestly at a loss for words." She looked down at the floor in shame.

"What's going on?" Paps came off as rude as he responded. 

"I-well...I was instructed to rebuild the core..." She stumbled over her words as she felt a rage build up inside of him. Instead of lashing out, he waited. "The Queen instructed me to-...I'm so sorry Papyrus..."

"Keep talking." 

"It was nearing completion when-...well when I heard strange sounds coming from the output chamber." She adjusted her lab coat and glasses before she finished. "You know- the uhm...the chamber that drains the unwanted materials from the core."

"Yeah, I know...I helped build the fucking thing." Paps replied in annoyance. 

She became flustered but continued. "When I went to investigate, the chamber was clogged with...well-" She hesitated as the touched the doorknob to Room 4B. 

Papyrus had no patience for her stammering. He carefully but sternly moved her aside as he violently pushed the door open. He stood in shock at what was before him and his body became weak. Kneecaps buckled under him as his brother And Undyne attempted to assist.

Blue gave a concerning look to Undyne as she attempted to speak. "I-im so sorry, Paps. This is- I couldn't do this without help...I didn't know what to do."

"Have you alerted the Queen?" Blue asked as he looked away from what was before them.

"No- s-hould I have? I don't real-"

"No." Papyrus spoke with a broken voice. "She can't find out about this."

"Pappy...She needs to-" 

"No!" He snapped. They remained quiet and allowed him to gather his emotions. He took another long look at the problem before him...The lifeless amalgamite with a familiar face imprisoned within a chamber of fluid.

This was the face that tortured him at night...The broken face of the once royal scientist, Gaster. Paps felt as if his soul was going to shatter as he held down the feeling of pure rage. Instead of acting on fear, he stood wearily and began approaching the glass. For a moment, the reflection of his own, tired and beaten face overlapped Gasters now cracked and soulless one. Paps could feel the magic flaring in his own eye as he struggled to stand.

As if in a horror film, Gasters face lit up with an amused, sadistic expression that startled Papyrus from his upright position. Hands bearing large holes slid down the inside of the glass as a purple aura surrounded the fluid inside. Undyne quickly touched a button beside the vat that ultimately shocked the awaken amalgamite back into his lifeless state. 

Blue approached his now sitting older brother and attempted to console him. Papyrus flinched violently in a pissed off like motion.

"Pappy." He said. "Let's leave, okay?" He looked at Undyne passively as he helped his brother stand. The weak form drooped depressingly against the shorter skeleton as they walked out of the room...leaving behind the nightmare that couldn't be ignored.


	2. Chapter Two

Papyrus stood, leaning against a sturdy rail that separated him from the void. He stood in the very same spot he had pushed Gaster to his death years ago. He hadn't truly realized how far of a drop the fall would have been until now that he was gazing into its depths. The darkness surrounded the space below him almost lovingly. 

He remembered why he did it. The scientist had gone after his brother. Papyrus had agreed that he would cooperate and endure constant conditioning to his psyche and his magic to become the ultimate weapon for the war against humans, if his brother were left untouched. Blue served as a great motivator. Gaster kept his end of the deal until he decided that he was ultimately the owner of his weapon and he wanted another. Gaster had waited for Papyrus to become so physically weak from the torture that he slept, unaware that just down the hall, Blue was taken to the concentrator. 

This machine would focus magical energy straight to the psyche so that it could be called upon when it's host became threatened or injured. His brother was not meant for war, Papyrus did all he could to keep his brother from experiencing so much pain....this included murdering the royal scientist.

He knew the consequences that would arise from doing this...however the core had exploded after Gasters body was thrown into the void. This served as a cover-up although Papyrus became severely injured himself. 

The return of Gasters body, no matter the form, served a problem for him..not only psychologically, but legally. He had been a royal judge although he harbored the same disgusting sin that crawled on his spine. 

Blue startled him out of his thoughts, he nearly dropped his cigarette into the core. 

"You doing okay?" His brother asked, not wanting to get so close to the edge of the walkway that hovered them over certain death.

He let out a sigh before replying. "I'm definitely not okay about it."

Blue looked up at his brother, he knew his Paps held dark secrets from him but he never pestered the other.

"I know that the royal scientist was a pretty terrible man, paps...but he's alive." Blue exclaimed. "He was making so much progress to get us to the surface..." Anger built up in Papyrus as he listened to his brother practically praise the man that caused his life to shatter into sheer misery. "I don't remember anything, really." Blue continued. "I think we need to alert the Queen, Paps...He could start helping Undyne wit-"

"Are you serious, Blue?" Papyrus practically yelled as he watched his brother recoil. "This man...deserved to die. He actually deserved worse than that. Do you really not remember anything!?" He shouted. "Because I sure as fuck do. Every. Single. Time...I close my eyes at night." Magic flared as he attempted to stay calm.

"Blue..." He rested his hands on his brothers shoulders firmly. "I killed this guy." The younger brothers eyes widened, looking at his older brother in disbelief. "He was gonna hurt-cha...Blue." The emotion that swelled behind his face urged tears to swell behind his magic. "I deserve everything he did'ta me...but you didn't." He paused. "I...I pushed him in the core."

The shorter brother held his now kneeling brother along his shoulders. 

"What do I fucking do about this??" He cried, allowing Blue to pat his back comfortingly.

In Room 4B, Gaster had honed in on the magical energy Paps was emitting due to his strong feeling of rage. "He was never careful enough." He thought as his amalgamation allowed him to escape the vat. He formed into the man he used to be, the only change being the damage he obtained to his face. Time had ceased to exist as he eyed Undyne frozen in mid panic from his outbreak. He walked briskly to the hall, navigating easily as he remembered his whereabouts. 

Paps felt a strange energy in the air...it was almost suffocating. He looked up at his brother who became still, frozen in place. Papyrus stood, magic at the ready for an unwanted guest that appeared before him.

"My weapon." He spoke as he stood calmly in front of the other.

Gasters voice put Papyrus into such a state of shock that all he could do was grip the railing to prevent himself from collapsing. 

"You never could control your emotions." This form of pure evil smirked. 

Papyrus gained amusement from the scientist before him. "You're smilin' a whole awful lot for someone who got their face all fucked up from that "accident" ya had." 

"I truly wonder what caused that." Gaster mused. "Surely my dear weapon I so charmingly created didn't attempt to kill me." His form dissipated and emerged directly in front of Papyrus, who's back was now against the railing. 

Gaster laughed as he watched Papyrus remain unmoved and calm. "Its almost as if you want to die."

"Tibia honest...it's kinda my dream actually." He smiled, knowing that any reaction would fuel the other.

"Hmm..." Gaster frowned. "I could throw you into the void right now, however that would be a waste of a perfectly good creation." He leaned in, extremely too close to for the others comfort, and inhaled. "You smell like you've been doing some self destructing already. Is the smoking necessary?" 

"I do all I can to try and kill myself." Papyrus snarled. "Keeps me from thinking about how fucking awful you are."

Gaster quickly grasped his throat, smiling wildly as he forced Papyrus backwards. "It would take minimal effort for me to fulfill your wish. Sadly..." He paused, frowning. "I'm only an illusion." 

Papyrus felt the floor beneath him rattle. He felt this before when the core had exploded...he glanced at the ground below him before looking back at Gaster whose form began to disperse. Time returned as he heard his brother calling out to him. He became instilled with fear when the sonic boom of the core illuminated the his vision in a bright flashing light. He looked at his brother who was now screaming his name with tears flooding his face.

Papyrus couldn't feel anything. His body became light and he felt as if he were being cradled caringly. "Death." He thought to himself. "Death was the ultimate goal."


	3. Chapter Three

*Underfell*

Papyrus laid amongst rubble, his chest being crushed under what seemed to be large debris from machinery. He couldn't feel his limbs or even his face for that matter. He did all he could to summon even the snallest bout of magic to assist him in escaping but the magic refused to flow through his fingertips.

"SANS!!?" He heard a voice from far off. "SAAAANS!!!?" Panic settled into his being as he was reminded that his Sans was also present during the explosion. 

He kicked and struggled against the large sheet of metal until it began to move. One final push released him from its grips and as he gasped for air, attempting to stand. Papyrus's legs were so physically weak from his injuries that he stammered, falling only a few inches from where he had laid.

He suddenly heard footsteps approaching quickly as if whoever it was were running. Papyrus attempted to see who or what was coming to his aid only to find that this monster...This monster looked terrifying. Papyrus was sure that if he were noticed, he would be killed, yet the large skeleton was heading right his way, hands orange with flowing magic.

Papyrus winced as this tower of a monster halted, kneeling beside him and grabbing an arm. 

"N-no!" Papyrus coughed, fighting to stay on the ground as he was pulled even harder to stand upright. His wrist was being held so tightly that he felt as if he'd break a bone. Instead of feeling pain, he felt warmth. Papyrus glanced, noting the healing magic that was bombarding his entire being. It felt...nice. Inviting. Comforting...

He allowed the monster to grab onto him and fling him over the others shoulder. He immediately felt defeat, burying his face in a piece of red clothing that smelled sweet, yet at the same time, extremely spicy.

It looked like a war zone around them. Rubble, flying debris as well as small explosions off in the distance. His saviour kept running, looking for any signs of life. 

He came upon a toppled over generator and faltered, nearly dropping the other. A faint red glow illuminated the air around them. Papyrus was dropped as the tall monster sprinted. He grabbed the bottom edge of the massive generator as it slightly lifted. Papyrus heard loud growling coming from him as both hands were shooting magic wildly, as if he were exerting every possible reservoir of energy he could muster to topple over the generator, revealing a relatively smaller monster underneath.

"SANS!" This monster shook, grabbing lifeless arms and attempting to pull the other upward. 

Papyrus began hearing low explosions from underground as he watched the other unfazed by the imminent danger. He mustered all of his strength to run (or rather stammer) to the taller skeleton. He grabbed an arm ushering him up.

"We have to go!" Papyrus yelled. 

"I'M NOT LEAVING SANS!"

"Then take him with-" Papyrus was cut off by the vibration of a nearby explosion. He gripped the others shoulder and dangerously teleported. 

\-------------------------------------------------------------  
The void was quiet. He still had the two other unknown monsters in tow however they seemed unonscious.

Papyrus knew he had fucked up...teleporting when he wasn't even sure where he was and he didn't have a destination in mind. He cursed under his breath as they floated. "I wish the explosion would have killed us." He thought. "Better than floating around the void for an eternity." He closed his eyes and momentarily took in the peacefulness that the void had to offer. 

Suddenly he felt hands tugging at them, pulling them forward. Papyrus noticed the amalgamated form immediately before attempting to kick himself free.

"My weapons." Gaster voice echoed throughout the void. Papyrus recoiled in terror as multiple hands formed around his face as well as the face of the smaller skeleton.

"It's been so long." 

Papyrus grimaced, refusing to respond.

"Dont look at your creator like that. I'm trying to make things right, Papyrus." Gaster showed his face amongst the darkness. 

"Tryin' to kill me is your way of makin' things right?" Papyrus asked. 

"Trust me, pet. The core explosion was a foreseen event. I cradled you in the void as long as I could to save your life."

Papyrus did remember being in the void before he woke up amongst the rubble...but that didn't negate the fact that he hated Gaster with every fiber of his being. 

"Believe it or not, I watch over you through the void to ensure your death isn't permanent." Gaster allowed the void to playfully tug at Papyrus's sweater. "All those times you attempted to kill yourself?" He mused. "I forced your brother awake so that he'd find you." 

Gasters gaze focused on the small unconscious skeleton. "However you're not my only creation." Darkness cradled his form. "I'm sending you back to your timeline, however these two will have to accompany you for the time being."

**Author's Note:**

> My Gaster is also the Gaster for other aus. Enjoy!


End file.
